'Thor: Rangarok' will feature Mark Ruffalo's Hulk to fight alongside Chris Hemsworth's Thor in a new Marvel deal. The film is considered the first ever to feature the Hulk outside the popular 'Avengers' franchise. Ruffalo's character is yet to have his own standalone film in the Marvel Cinematic Universe (MCU).

According to Variety, Ruffalo will return to the big screen as Bruce Banner a.k.a. the Hulk as he is currently in final negotiations with Marvel. Chris Hemsworth will also reprise his role as the titular God of Thunder. Tom Hiddleston and Jaimie Alexander will also return as Loki and Lady Sif, respectively.

Another article by the Daily Mail reported that Ruffalo's appearance on 'Thor: Ragnarok' will be the first ever outside the 'Avengers' franchise. It remains unknown what Hulk's role in the film will be. Ruffalo is the fourth actor to take on the iconic green superhero on the big screen joining the likes of Edward Norton who starred in 'The Incredible Hulk', Lou Ferrigno in 'Avengers: Age of Ultron', and Eric Bana in 'Hulk'.

Although further plot details have yet to be released, the upcoming film is said to take place in a world separate from Earth or Asgard. According to The Cheat Sheet, the title itself, 'Ragnarok', may indicate the apocalyptic series of events that may occur within the third installment. It means "the end of days" in Norse mythology.

It was reported that a character known as the Valkyrie (Brunnhilde) will be introduced. In the comic books, she is a powerful Asgardian warrior who possesses superhuman abilities of strength, speed, stamina, reflexes and agility. She also has strong depth perception and can transport herself and the dead to another dimension.

So far, there has been no official casting news as to which actress will take up the role of Valkyrie should reports on the new character's appearance be accurate. Nevertheless, the rise of a strong female protagonist is imminent as it was previously reported that Alexander's Lady Sif will be given a considerably larger role compared to her previous ones. There have also been rumors of Natalie Portman's Jane Foster transforming into a female Thor.

'Thor: Ragnarok' is an upcoming action-fantasy film scheduled to be released on November 3, 2017. The film will will pick up after the events of 2013's 'Thor: The Dark World' and will be directed by Taika Waititi. It is the third film in the 'Thor' series, and is the fifth film in Phase Three of the MCU.